remove redundant initializations

Author: perazz

src/fpm_environment.f90

@@ -50,8 +50,6 @@ integer function get_os_type() result(r)
 
         first_run = .false.
         r = OS_UNKNOWN
-        length = 0
-        rc = 0
 
         ! Check environment variable `OSTYPE`.
         call get_environment_variable('OSTYPE', val, length, rc)

src/fpm_meta.f90

@@ -490,9 +490,6 @@ subroutine init_mpi(this,compiler,error)
 
     !> Cleanup
     call destroy(this)
-    fwrap = string_t("")
-    cwrap = string_t("")
-    cxxwrap = string_t("")
 
     !> Get all candidate MPI wrappers
     call mpi_wrappers(compiler,fort_wrappers,c_wrappers,cpp_wrappers)